I've been using a non-electronic macro tube, and I've also been looking at some of the ones with contact points on them. I was wondering, does anybody have any experience with using/buying these types of adapters, I'm looking for one, but I don't want it to fall apart easily. [link] Here's what I'm basically talking about.
The point of using one with contacts is that otherwise you have no way to control the aperture unless you have a lens with an aperture ring. Also, different brands of camera have different behaviours when you have no electronic connection to the body. Canon remain wide open, while I believe Nikon remain stopped down.
You still have the ability to switch to manual focus while using extension tube, so you don't hand over focus to the camera - but selecting the right depth of field in the first place may be important to you.
The lenses that I'm using do, because when I attach my normal tube to the camera and lens, the DOF automatically drops to F00, and return to normal when I attach the lens directly to the body. Focus is not really my main strain right now, it's just kind of getting on my nerves to not be able to control the DOF. Plus, I don't have the kind of money to drop on a full macro lens currently, I'm just looking for an alternative. Thanks for the help
Unfortunately, no Canon EF or EF-S lenses have manual aperture rings, so once the lens is mounted to a tube with no electronic pass-thru contacts, the aperture can not be adjusted.
However, the article at [link] describes a way to stop-down the lens before you mount it to the extension tubes...
Using older FD-mount lenses (which do have aperture rings) can be problematic. In addition to the lens, you'd need to buy an FD-to-EF adapter in order to mount the lend to the tubes - preferably one without any "corrective" optics in it.
Never used one myself, but I would imagine that getting one with contacts is pretty much a waste of money. You’d never leave the determination of a close-up focal plane to your camera.
Currently with the tube that I'm using, it's an entirely Manuel lens control. I have no control over the DOF though, and with the tube attached, it automatically remains at F00. I don't really have the money to drop on a full macro lens though, so I was looking for alternatives.
In that case, it might be worth looking for a cheap manual lens as a possible alternative. An older 50mm lens with a manual aperture should work, and ought to be quite sharp to boot.
[link]
Here's what I'm basically talking about.